/**
 * html2Json 改造来自: https://github.com/Jxck/html2json
 *
 *
 * author: Di (微信小程序开发工程师)
 * organization: WeAppDev(微信小程序开发论坛)(http://weappdev.com)
 *               垂直微信小程序开发交流社区
 *
 * github地址: https://github.com/icindy/wxParse
 *
 * for: 微信小程序富文本解析
 * detail : http://weappdev.com/t/wxparse-alpha0-1-html-markdown/184
 */

import wxDiscode from './wxDiscode'
import HTMLParser from './htmlparser'

function makeMap(str) {
	const obj = {}
	const items = str.split(',')
	for (let i = 0; i < items.length; i += 1) obj[items[i]] = true
	return obj
}

// Block Elements - HTML 5
const block = makeMap(
	'br,code,address,article,applet,aside,audio,blockquote,button,canvas,center,dd,del,dir,div,dl,dt,fieldset,figcaption,figure,footer,form,frameset,h1,h2,h3,h4,h5,h6,header,hgroup,hr,iframe,ins,isindex,li,map,menu,noframes,noscript,object,ol,output,p,pre,section,script,table,tbody,td,tfoot,th,thead,tr,ul,video'
)

// Inline Elements - HTML 5
const inline = makeMap(
	'a,abbr,acronym,applet,b,basefont,bdo,big,button,cite,del,dfn,em,font,i,iframe,img,input,ins,kbd,label,map,object,q,s,samp,script,select,small,span,strike,strong,sub,sup,textarea,tt,u,var'
)

// Elements that you can, intentionally, leave open
// (and which close themselves)
const closeSelf = makeMap('colgroup,dd,dt,li,options,p,td,tfoot,th,thead,tr')

function removeDOCTYPE(html) {
	const isDocument = /<body.*>([^]*)<\/body>/.test(html)
	return isDocument ? RegExp.$1 : html
}

function trimHtml(html) {
	return html
		.replace(/<!--.*?-->/gi, '')
		.replace(/\/\*.*?\*\//gi, '')
		.replace(/[ ]+</gi, '<')
		.replace(/<script[^]*<\/script>/gi, '')
		.replace(/<style[^]*<\/style>/gi, '')
}

function getScreenInfo() {
	const screen = {}
	wx.getSystemInfo({
		success: (res) => {
			screen.width = res.windowWidth
			screen.height = res.windowHeight
		},
	})
	return screen
}

function html2json(html, customHandler, imageProp, host) {
	// 处理字符串
	html = removeDOCTYPE(html)
	html = trimHtml(html)
	html = wxDiscode.strDiscode(html)
	// 生成node节点
	const bufArray = []
	const results = {
		nodes: [],
		imageUrls: [],
	}

	const screen = getScreenInfo()
	function Node(tag) {
		this.node = 'element'
		this.tag = tag

		this.$screen = screen
	}

	HTMLParser(html, {
		start(tag, attrs, unary) {
			// node for this element
			const node = new Node(tag)

			if (bufArray.length !== 0) {
				const parent = bufArray[0]
				if (parent.nodes === undefined) {
					parent.nodes = []
				}
			}

			if (block[tag]) {
				node.tagType = 'block'
			} else if (inline[tag]) {
				node.tagType = 'inline'
			} else if (closeSelf[tag]) {
				node.tagType = 'closeSelf'
			}

			node.attr = attrs.reduce((pre, attr) => {
				const { name } = attr
				let { value } = attr
				if (name === 'class') {
					node.classStr = value
				}
				// has multi attibutes
				// make it array of attribute
				if (name === 'style') {
					node.styleStr = value
				}
				if (value.match(/ /)) {
					value = value.split(' ')
				}

				// if attr already exists
				// merge it
				if (pre[name]) {
					if (Array.isArray(pre[name])) {
						// already array, push to last
						pre[name].push(value)
					} else {
						// single value, make it array
						pre[name] = [pre[name], value]
					}
				} else {
					// not exist, put it
					pre[name] = value
				}

				return pre
			}, {})

			// 优化样式相关属性
			if (node.classStr) {
				node.classStr += ` ${node.tag}`
			} else {
				node.classStr = node.tag
			}
			if (node.tagType === 'inline') {
				node.classStr += ' inline'
			}

			// 对img添加额外数据
			if (node.tag === 'img') {
				let imgUrl = node.attr.src
				imgUrl = wxDiscode.urlToHttpUrl(imgUrl, imageProp.domain)
				Object.assign(node.attr, imageProp, {
					src: imgUrl || '',
				})
				if (imgUrl) {
					results.imageUrls.push(imgUrl)
				}
			}

			// 处理a标签属性
			if (node.tag === 'a') {
				node.attr.href = node.attr.href || ''
			}

			// 处理font标签样式属性
			if (node.tag === 'font') {
				const fontSize = [
					'x-small',
					'small',
					'medium',
					'large',
					'x-large',
					'xx-large',
					'-webkit-xxx-large',
				]
				const styleAttrs = {
					color: 'color',
					face: 'font-family',
					size: 'font-size',
				}
				if (!node.styleStr) node.styleStr = ''
				Object.keys(styleAttrs).forEach((key) => {
					if (node.attr[key]) {
						const value =
							key === 'size'
								? fontSize[node.attr[key] - 1]
								: node.attr[key]
						node.styleStr += `${styleAttrs[key]}: ${value};`
					}
				})
			}

			// 临时记录source资源
			if (node.tag === 'source') {
				results.source = node.attr.src
			}

			if (customHandler.start) {
				customHandler.start(node, results)
			}

			if (unary) {
				// if this tag doesn't have end tag
				// like <img src="hoge.png"/>
				// add to parents
				const parent = bufArray[0] || results
				if (parent.nodes === undefined) {
					parent.nodes = []
				}
				parent.nodes.push(node)
			} else {
				bufArray.unshift(node)
			}
		},
		end(tag) {
			// merge into parent tag
			const node = bufArray.shift()
			if (node.tag !== tag) {
				console.error('invalid state: mismatch end tag')
			}

			// 当有缓存source资源时于于video补上src资源
			if (node.tag === 'video' && results.source) {
				node.attr.src = results.source
				delete results.source
			}

			if (customHandler.end) {
				customHandler.end(node, results)
			}

			if (bufArray.length === 0) {
				results.nodes.push(node)
			} else {
				const parent = bufArray[0]
				if (!parent.nodes) {
					parent.nodes = []
				}
				parent.nodes.push(node)
			}
		},
		chars(text) {
			if (!text.trim()) return

			const node = {
				node: 'text',
				text,
			}

			if (customHandler.chars) {
				customHandler.chars(node, results)
			}

			if (bufArray.length === 0) {
				results.nodes.push(node)
			} else {
				const parent = bufArray[0]
				if (parent.nodes === undefined) {
					parent.nodes = []
				}
				parent.nodes.push(node)
			}
		},
	})

	return results
}

export default html2json
